CELL STRUCTURES AND FUNCTION
CELL DIVISION
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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centrosome, centromere
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centromere, centrosome
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centromere, nucleus
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None of the above
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Detailed explanation-1: -The centromere appears as a constricted region of a chromosome and plays a key role in helping the cell divide up its DNA during division (mitosis and meiosis). Specifically, it is the region where the cell’s spindle fibers attach.
Detailed explanation-2: -The two “sister” chromatids are joined at a constricted region of the chromosome called the centromere.
Detailed explanation-3: -Spindle fibers from one side of the cell attach to one of the sister chromatids. The spindle fibers from the other side of the cell attach to the other sister chromatids of the chromosome. They attach at a point called the kinetochore, which is a disk or protein that is on each side of the centromere.
Detailed explanation-4: -Metaphase. During metaphase, spindle fibers attach to the centromere of each pair of sister chromatids (see Figure below). The sister chromatids line up at the equator, or center, of the cell. This is also known as the metaphase plate.
Detailed explanation-5: -Microtubules of the spindle apparatus attach to the chromatids via complex protein structures called kinetochores, which assemble at a unique location on each chromosome called a centromere (Figure 1, top row, panel iii.).